summaryrefslogtreecommitdiff
path: root/drivers/thunderbolt/ctl.h
AgeCommit message (Collapse)Author
2017-06-09thunderbolt: Rework control channel to be more reliableMika Westerberg
If a request times out the response might arrive right after the request is failed. This response is pushed to the kfifo and next request will read it instead. Since it most likely will not pass our validation checks in parse_header() the next request will fail as well, and response to that request will be pushed to the kfifo, ad infinitum. We end up in a situation where all requests fail and no devices can be added anymore until the driver is unloaded and reloaded again. To overcome this, rework the control channel so that we will have a queue of outstanding requests. Each request will be handled in turn and the response is validated against what is expected. Unexpected packets (for example responses for requests that have been timed out) are dropped. This model is copied from Greybus implementation with small changes here and there to get it cope with Thunderbolt control packets. In addition the configuration packets support sequence number which the switch is supposed to copy from the request to response. We use this to drop responses that are already timed out. Taking advantage of the sequence number, we automatically retry configuration read/write 4 times before giving up. Also timeout is not a programming error so there is no need to trigger a scary backtrace (WARN), instead we just log a warning. After all Thunderbolt devices are hot-pluggable by definition which means user can unplug a device any time and that is totally acceptable. With this change there is no need to take the global domain lock when sending configuration packets anymore. This is useful when we add support for cross-domain (XDomain) communication later on. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com> Reviewed-by: Michael Jamet <michael.jamet@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andreas Noever <andreas.noever@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09thunderbolt: Let the connection manager handle all notificationsMika Westerberg
Currently the control channel (ctl.c) handles the one supported notification (PLUG_EVENT) and sends back ACK accordingly. However, we are going to add support for the internal connection manager (ICM) that needs to handle a different notifications. So instead of dealing everything in the control channel, we change the callback to take an arbitrary thunderbolt packet and convert the native connection manager to handle the event itself. In addition we only push replies we know of to the response FIFO. Everything else is treated as notification (or request) and is expected to be dealt by the connection manager implementation. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com> Reviewed-by: Michael Jamet <michael.jamet@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andreas Noever <andreas.noever@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09thunderbolt: Expose make_header() to other filesMika Westerberg
We will be using this function in files introduced in subsequent patches. While there the function is renamed to tb_cfg_make_header() following tb_cfg_get_route(). Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com> Reviewed-by: Michael Jamet <michael.jamet@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andreas Noever <andreas.noever@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09thunderbolt: Expose get_route() to other filesMika Westerberg
We are going to use it when we change the connection manager to handle events itself. Also rename it to follow naming convention used in functions exposed in ctl.h. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com> Reviewed-by: Michael Jamet <michael.jamet@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andreas Noever <andreas.noever@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09thunderbolt: Move control channel messages to tb_msgs.hMika Westerberg
We will be forwarding notifications received from the control channel to the connection manager implementations. This way they can decide what to do if anything when a notification is received. To be able to use control channel messages from other files, move them to tb_msgs.h. No functional changes intended. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com> Reviewed-by: Michael Jamet <michael.jamet@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andreas Noever <andreas.noever@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-09thunderbolt: Use const buffer pointer in write operationsMika Westerberg
These functions should not (and do not) modify the argument in any way so make it const. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Yehezkel Bernat <yehezkel.bernat@intel.com> Reviewed-by: Michael Jamet <michael.jamet@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andreas Noever <andreas.noever@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-19thunderbolt: Add control channel interfaceAndreas Noever
Thunderbolt devices are configured by reading/writing into their configuration space (similar to pci). This is done by sending packets through the NHI (native host interface) onto the control channel. This patch handles the low level packet based protocol and exposes higher level operations like tb_cfg_read/tb_cfg_write. Signed-off-by: Andreas Noever <andreas.noever@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>